Visualization of grapevine root colonization by the Saharan soil isolate Saccharothrix algeriensis NRRL B-24137 using DOPE-FISH microscopy

Background and aim There is currently a gap of knowledge regarding whether some beneficial bacteria isolated from desert soils can colonize epi- and endophytically plants of temperate regions. In this study, the early steps of the colonization process of one of these bacteria, Saccharothrix algeriensis NRRL B-24137, was studied on grapevine roots to determine if this beneficial strain can colonize a non-natural host plant. An improved method of fluorescence in situ hybridization (FISH), the double labeling of oligonucleotide probes (DOPE)-FISH technique was used to visualize the colonization behavior of such bacteria as well as to determine if the method could be used to track microbes on and inside plants. Methods A probe specific to Saccharothrix spp. was firstly designed. Visualization of the colonization behavior of S. algeriensis NRRL B-24137 on and inside roots of grapevine plants was then carried out with DOPE-FISH microscopy. Results The results showed that 10 days after inoculation, the strain could colonize the root hair zone, root elongation zone, as well as root emergence sites by establishing different forms of bacterial structures as revealed by the DOPE-FISH technique. Further observations showed that the strain could be also endophytic inside the endorhiza of grapevine plants. Conclusions Taking into account the natural niches of this beneficial strain, this study exemplifies that, in spite of its isolation from desert soil, the strain can establish populations as well as subpopulations on and inside grapevine plants and that the DOPE-FISH tool can allow to detect it

Functional outcomes in symptomatic versus asymptomatic patients undergoing incisional hernia repair: Replacing one problem with another? A prospective cohort study in 1312 patients

Background: Incisional hernias can be associated with pain or discomfort. Surgical repair especially mesh reinforcement, may likewise induce pain. The primary objective was to assess the incidence of pain after hernia repair in patients with and without pre-operative pain or discomfort. The secondary objectives were to determine the preferred mesh type, mesh location and surgical technique in minimizing postoperative pain or discomfort. Materials and methods: A registry-based prospective cohort study was performed, including patients undergoing incisional hernia repair between September 2011 and May 2019. Patients with a minimum follow-up of 3–6 months were included. The incidence of hernia related pain and discomfort was recorded perioperatively. Results: A total of 1312 patients were included. Pre-operatively, 1091 (83%) patients reported pain or discomfort. After hernia repair, 961 (73%) patients did not report pain or discomfort (mean follow-up = 11.1 months). Of the pre-operative asymptomatic patients (n = 221), 44 (20%, moderate or severe pain: n = 14, 32%) reported pain or discomfort after mean follow-up of 10.5 months. Of those patients initially reporting pain or discomfort (n = 1091), 307 (28%, moderate or severe pain: n = 80, 26%) still reported pain or discomfort after a mean follow-up of 11.3 months postoperatively. Conclusion: In symptomatic incisional hernia patients, hernia related complaints may be resolved in the majority of cases undergoing surgical repair. In asymptomatic incisional hernia patients, pain or discomfort may be induced in a considerable number of patients due to surgical repair and one should be aware if this postoperative complication

Mise au point d'un modèle de simulation de la rouille brune du blé

Cette étude présente un modèle de simulation de la rouille brune du blé, dont l'agent pathogène, Puccinia recondita f sp tritici, est le principal parasite des parties aériennes du blé dans le Sud-Ouest de la France. Le système mis en forme est un modèle déterministe, qui simule l'ensemble du cycle de l'agent pathogène. Il utilise des données climatiques trihoraires (température et humectation) pour simuler les différentes phases de l'évolution de la maladie et intègre certains paramètres d'ordre phénologique et agronomique. Le modèle a été validé sur plusieurs années. La comparaison des courbes d'évolution des pustules infectieuses réelles et simulées montre globalement que ce système permet aujourd'hui de simuler correctement l'évolution de l'agent pathogène. Ainsi, de par sa conception et son organisation, il pourra être utilisé en tant qu'indicateur de risques et contribuer à l'amélioration des avertissements agricoles, mais aussi en tant que modèle d'aide à la décision à la parcelle dans le cadre notamment du raisonnement des interventions fongicides et de l'interprétation des résultats d'expérimentations des produits phytosanitaires.A model of simulation of wheat leaf rust. Puccinia recondita f sp tritici is the most important disease of wheat in the south-west of France. The authors propose a model of simulation which is an indicator model of risk. It makes it possible to simulate the evolution of the wheat leaf rust (figs 1, 2). It uses climatic data to simulate various phases of the evolution of the disease; temperature and free moisture (fig 3) seem to be the main limiting factors in the infectious process for our regions. It also quantifies the stages of development of the fungus (figs 4, 5). This method has been tested for several years. A good correlation between the simulations of disease by the model and the field observations has been shown (fig 6). It can therefore be useful for fungicide trials as well as for diffusion of agricultural forecasts

Diversity and Role of Endophytic and Rhizosphere Microbes Associated with Hyperaccumulator Plants During Metal Accumulation

Phytomining can be limited by low biomass productivity by plants or limited availability of soil metals. Ongoing research attempts to overcome these potential constraints and to make phytomining a successful commercial technique in the recovery of metals from polluted or naturally metal-rich soil by (hyper) accumulating plants. Recently, the benefits of combining phytoremediation with bioremediation, which uses beneficial microorganisms such as endophytic or rhizosphere bacteria and fungi for metal removal from soils, have been demonstrated. Metal-resistant microorganisms play an important role in enhancing plant survival and growth in these soils by alleviating metal toxicity and supplying nutrients. Furthermore, these beneficial microorganisms are able to enhance metal bioavailability in the rhizosphere of plants. An increase in plant growth and metal uptake increases the effectiveness of phytoremediation processes coupled with bioremediation. Here, we discuss how abiotic factors, such as the presence of metals in polluted sites or in naturally metal-rich (ultramafic) soils modulate activities of soil microbial communities. Then we introduce the concept of microbe-assisted phytomining and underline the role of plant-associated microorganisms in metal bioavailability and uptake by host plants that has attracted growing interest over the last decade. Finally, we present various techniques, including phenotypic, genotypic, and metagenomic approaches, which allow for characterizing soil microbial community structure and diversity and endophytic community in polluted or naturally metal-rich soils.Peer reviewe